Wednesday, 24 May 2017

Three views capturing some of the bits that have recently been grit blasted, which provide a flavour for activities later this year.

The big bits in the foreground of this image include the (from right to left), the covers for the cam shaft/ valve push rods and the gear train from the MDB4 engine (see photo below), followed by the cover for the gear wheel on the lay shaft, which forms part of the final drive and the casting which carries the starting mechanism (see 8th March 2017 update)

This is the final drive from the gear box to the lay shaft, which is protected by the cover in the centre of the first image. The ‘shadow’ of the cover can be seen. The upper strap of the transmission brake is also visible in this view.

The large wheel on the left of the view is the drum for the transmission brake. Other transmission brake components on view include the two crescent shaped plates (centre) and the brake shoes (rear), see 8th March 2017 update for the relationship of the transmission brake bits. The other components visible include the drive pulley for the water pump/ fan belt, a cab stanchion, parts from the lay shaft and the engine starting mechanism.

Photos by Rob Bishop
After two years lying on their back, the frames have now been turned over and are now the right way up, so here are a few general views to place the various components into context. This photo from the rear of the loco shows the sub-frames in position, with the spring pockets bolted on and also the brackets for the brake gear fitted to the underside of the floor. The brake weigh shaft is to the left, under the cab floor and the angles which will carry the drag box can be seen behind the front buffer beam. Dave Hatt is about to put in a cameo appearance to rivet in the upper drag box angles.

This view from the front clearly shows the welded in repair to the rear frame stretcher (bottom)

Frames right side up:

July 2015

April 2017

Engine Mounts

Contrasting views of the engine mounts before and after:

The semi-circular mount was for the dynamo. The heavily rusted cab floor plate was originally riveted in. The replacement will be fitted with set screws to allow access to the dragbox for maintenance.

While the upper surface of the floor is heavily pitted, it is still fit for purpose and has been retained, in line with the conservation ethos of the project.

Friday, 19 May 2017

Photos by Rob Bishop
The next few photos of odd bits of bar will make a lot more sense if you understand how the brake gear works. The pull rods act on two suspension arms, on the centreline of the loco. The suspension arms act in turn on two short links which pull on the carrying arms which carry the brake blocks. The carrying arms are themselves hung from two suspension links, all coloured luminous green in the section below.

These are the brackets for the suspension links. Central bracket for the pull rod link, outer brackets for the carrying arm.

The rear assembly. This pivots from the frame via the top hole, with the pull rod acting on the bottom hole. The brake block bolts to the outer hole on the carrying arm while the inner hole is for a clevis to carry the suspension arm. The carrying arms are shaped to clear the flanges.

The carrying arms, fitted with clevises for the suspension arms. Note the rather crude flame cut finish.

Both carrying arms complete with suspension links.

The suspension links fitted to the frames. This is the front unit. The bracket on the central link is for a release spring, which connects via a hook to the hole in frames. This spring pulls the brakes off the wheels when they are released.

Thursday, 18 May 2017

The lack of recent news does not reflect a lack of recent progress. This report focuses on ‘new’ construction. KS4415 has never had a ‘drag box’ per se, merely couplings and buffers attached to the buffer beam. In early 1929, KS4415 was fitted with chopper couplings to allow it to be used on passenger trains on the WHR. This is the period the restoration aims to represent. How the chopper couplings were fitted is unclear. Getting the coupling arrangement right is essential for the safe operation of the locomotive so we are shamelessly adopting current technology. To provide an idea about what we are currently fitting, here is ‘the answer’, in this case fitted to new FfR observation car 152.

Dragbox Assembly Car 152

The drawbar pivots in a crosshead. The crosshead is supported on two large bolts, with a series of rubber pads providing springing for both haulage and buffing loads. On KS4415 space to install this arrangement is limited, so rather than being fixed to a frame stretcher the dragbox assembly will be fixed to a strengthened buffer beam.

One of the crossheads for KS4415

The bufferbeam marked out for the new slot to accommodate the coupling

Spare’ holes welded up, and new slot cut

A doubling plate has been fitted inside the frames

Having welded the old holes up Matty Wolstenholme drills a new row of holes. These will be used to rivet a pair of angles inside the frames which will carry the dragbox.

New holes, meet old holes

The angles used to fit the drag boxes to the frames have been riveted in. The two bars labelled ‘top’ and ‘bottom’ are the start of the dragbox and are bolted to the angles.